This invention relates to fluid flow lines having a sight tube interposed therein and, more particularly, to a self-cleaning assembly for such a sight tube.
There are numerous applications wherein fluid flow lines have a transparent section so that the flow is visible therethrough, such visibility often being desirable to provide a quick check of the operative status of a system. In a system where the flowing fluid comprises suspended particulate matter, particles often adhere to and accumulate on the interior wall of the flow line. This is undesirable because it reduces visibility through the transparent section of the flow line. It is therefore an object of the present invention to provide an assembly for scouring the interior wall of the transparent section of a fluid flow line to remove particles that have accumulated thereon.
Such an assembly preferably should not require an external power source and should use only the power which is available from the fluid flow. It should not damage the sight tube and not become fouled by particles in the fluid stream. Further, the assembly should present minimal restriction to fluid flow.
It is therefore a more specific object of this invention to provide such an assembly which is operative in response to fluid flow so that no external activation or energization of the assembly is required in order to effect the cleaning function.
It is another object of this invention to provide such an assembly which is self cleaning so that it does not become fouled by particles in the fluid stream and which presents minimal restriction to fluid flow.